let animal = { name: '动物' }
let cat = {
  __proto__: animal,
  name: '小猫',
  show() {
    console.log(super.name)
  },
  getName: () => {
    console.log(this.name || '未知')
  },
}
cat.show()
cat.getName()

console.log(Symbol('desc') === Symbol('desc'))
